The invention is directed to a thrust grating cooler for cooling hot material, for example cement clinker emerging from a rotary tubular kiln.
In a thrust grating cooler, the grate system is composed of a plurality of stationary and movable grating plate carriers. A plurality of grating plates are secured to the carriers and are provided with openings for cooling air and traversed by cooling air essentially from bottom to top. As viewed in a conveying direction, rows of stationary grating plates are secured by means of their stationary grate plate carriers to the lower part of the cooler housing or to the sidewalls of the cooler housing. These stationary rows alternate with reciprocally movable rows of grating plates that are secured in common by their correspondingly reciprocally movable grate plate carriers to one or more C-shaped push frames. The C-push frames are mounted so as to be longitudinally movable. The drive of the C-push frames is provided by drives installed outside the lower part of the housing, for example by slider-crank mechanisms or hydraulic cylinders. As a result of the common, oscillatory motion of all of the movable rows of grating plates, the material to be cooled is conveyed in batches over the rows of grating plates having air flowing upwardly therethrough and is thereby cooled.
When the grate plate carriers are formed as hollow beams arranged transversely relative to the longitudinal axis of the cooler and through which the cooling air is brought to the individual grating plates, difficulties arise in having the cooling air flow into the reciprocally movable grating plate carriers. Up to now, the reciprocally movable grating plate carriers were individually aerated with cooling air flowing through flexible hose conduits extending from stationary cooling air conduits positioned under the thrust gratings. The thrusting motion of the grating plate carriers caused a constant pendulating motion of the flexible air hose conduits that resulted in premature rupturing due to the frequent alternating bending stresses and due to the simultaneous wear as a result of the fine cooling air dust adhering thereto. This rupturing of the cooling hoses is a serious problem which can cause shutdowns of the clinker cooler as well as shutdowns of an entire cement clinker production line.